Water flows down a vertical wall that is 1 m tall and 0.25 m wide without any ripples. The flowrate is 0.014 kg/s. Oxygen is diffusing from the gas, which is saturated with water, into the liquid. The diffusivity of oxygen in liquid water is 2.5 x 10-5 cm2/s. The water in contact with the oxygen has an oxygen mole fraction of 2.3 x 10-4. The water entering the top of the wall contains no oxygen and is at 15.6C.

Find:

a. the film thickness, m

b. the fluid velocity, m/s

c. the Reynolds number

d. the Sherwood number, averaged over the length, for short contact times

e. the mass transfer coefficient, averaged over the length, for short contact times, mole/m2s

f. the rate of transfer of oxygen into the falling film, mole/s